Pre-Existing Condition Exclusion Period July 12, 2019 18:43 Updated The time period during which a health plan won't pay for care relating to a pre-existing condition. Under a job-based plan, this cannot exceed 12 months for a regular enrollee or 18 months for a late-enrollee. Related articles Chronic Disease Management Pre-Existing Condition How do I change plans? How to see if your health care provider is covered by your insurance plan Can't find your answer? Find local assistance or contact us.